GLAST blasts off in search of gamma rays

The GLAST gamma-ray telescope was launched into space at 12.05 p.m. local time from Cape Canaveral in Florida today. The instrument is due to orbit some 560 km above the Earth’s surface where it will begin its survey of gamma rays from throughout the universe. Physicists involved in the project hope that GLAST (the Gamma-ray Large Area Space Telescope) will help them study some of the most violent events in the universe, provide a new window into the early universe and even shed light on the origins of dark matter.

The four-tonne observatory is packed with state-of-the-art particle detectors including GLAST’s primary instrument — the Large Area Telescope (LAT), which will cover the energy band between 20 MeV and at least 300 GeV. A second instrument, the GLAST Burst Monitor (GBM), will detect transient sources such gamma-ray bursts and solar flares down to energies of just 8 keV.

It took a lot of people in many countries to make this 16-year journey come to fruition
Peter Michelson, Stanford University

GLAST must operate in space because gamma rays cannot penetrate even a few kilometres through Earth’s upper atmosphere. It is, though, possible to do some gamma-ray astronomy with ground-based telescopes by measuring the particles the gamma rays produce when they strike the matter in the atmosphere. However, such telescopes can only detect gamma-rays with energies of less than 100 GeV.

Gamma-ray bursts

One objective of the mission is to gain a better understanding of the origins of gamma-ray bursts. These poorly-understood events occur at a rate of about one per day, and briefly shine as the brightest objects in the universe. GLAST could allow to scientists to measure the total energy released in such bursts and the nature of their high-energy spectra — both of which have never been done.

GLAST will also target extreme events that occur in active galaxies when matter is accelerated to relativistic energies in a jet powered by a supermassive black hole. This results in the emission of gamma rays with a power equivalent to that of all the stars in an entire galaxy over all wavelengths. Until now, gamma-ray detectors have not been able to measure these highly variable emissions in any detail over long timescales, but GLAST will allow physicists to see into these jets, thus revealing their contents and dynamics.

GLAST will also support research in several areas in fundamental physics. One such opportunity is provided by the diffuse gamma-ray cosmic background — a poorly-understood haze of giga-electron-volt gamma rays that theorists currently attribute to cascades from distant tera-electron-volt gamma-ray sources, ultrahigh-energy cosmic rays, and even Hawking radiation emitted by primordial black holes.

Another area concerns one of the most fundamental questions in cosmology: the origin and distribution of dark matter. An important class of theories predicts the existence of weakly interacting massive particles, or WIMPs. In most models, WIMPs may annihilate in pairs, thus producing high-energy particles, including gamma rays. GLAST could be capable of detecting this radiation from annihilation events in the galactic halo, providing unique information about dark matter.

$690m price tag

The mission cost $690m and is a collaboration between NASA, the US Department of Energy and universities and research institutes in the US, Japan, Italy, France and Sweden.

“It took a lot of people in many countries to make this 16-year journey come to fruition,” says Peter Michelson, a physicist at Stanford University and principal investigator for the LAT.

Over the next two months the GLAST’s instruments will be tuned and calibrated. “First light”, when the telescope takes its first image of the sky, should happen in about four weeks and GLAST should start gathering data by mid-August.

Update 12 June 2008

After a 75 minute flight, GLAST settled into orbit and both of its solar arrays were deployed successfully.

Will Hawking Radiation finally be proven or not?

How much time might be required before analysis of GLAST data might indicate proof or rejection of Hawking Radiation theory?

This could be critical in determining the safety of the Large Hadron Collider, due to begin collisions later this year.

Unlike what CERN tells the public, the Large Hadron Collider Safety Assessment Group (LSAG) writes that current safety arguments are not valid proof of safety. Micro black holes might be created by the Large Hadron Collider, they might not evaporate, they might grow quickly and we have not been damaged by cosmic rays because cosmic rays pass harmlessly through Earth. CERN also tells the public that a new safety report has been completed, but so far the final report has not been released for review by world’s scientists.

The legal complaint before US Federal Court in Hawaii demands 4 months to review this safety report and a permanent injunction if safety can not be assured to within reasonable industry standards. First hearing is scheduled for June 16, 2008.

I Micro black holes might be created by the Large Hadron Collider, they might not evaporate, they might grow quickly and we have not been damaged by cosmic rays because cosmic rays pass harmlessly through Earth.

I would think that if micro black holes could settle in Earth's (or any other celestial object's) gravity well and be stable for anything less than a fraction of a second, than one would already be there. How could any star last very long?

I can't seem to figure out how fast such a black hole would be moving after being generated, but without a charge and likely having a high velocity, it must pass through the Earth above escape velocity.

Ahhh ... it is pleasure to see the succesful launch of this mission. this is true science. Guys, stop worrying about the micro black holes at the LHC. It will never start operating. I thought the latest schedule had it taking beam in May. It's almost mid June and the beam is a distant prognostication. I don't know how most of the people there get to keep their jobs. In any other industry they would have been fired a long time ago. Especially Aymar who makes false statements (knowing htat they are false) to the media about the start dates.

It would be a thing of exquisite perversity if GLAST finds dark matter evidence before the LHC.

Hawking Radiation

Before one can start to think of Hawking Radiation (HR) as a real thing, I guess they ought first to ponder deeper on the theory upon which it (HR) is based is "correct". Sure the General Theory of Relativity (GTR) contains an element of truth - no doubt about this, but I would like to believe that black-holes, despite their popularity, signal the demise of Einstein's GTR. Its like we are over stretching the GTR. Only until a truly Unified Field Theory is in place, can we begin to talk of such exotic things a black holes. This is my take.

Ahhh ... it is pleasure to see the succesful launch of this mission. this is true science. Guys, stop worrying about the micro black holes at the LHC. It will never start operating. I thought the latest schedule had it taking beam in May. It's almost mid June and the beam is a distant prognostication. I don't know how most of the people there get to keep their jobs. In any other industry they would have been fired a long time ago. Especially Aymar who makes false statements (knowing htat they are false) to the media about the start dates.

It would be a thing of exquisite perversity if GLAST finds dark matter evidence before the LHC.

You know well that the LHC is scheduled to start operation in July (physicsworld.com…33600 ), and Aymar is no longer the director. As I mentioned elsewhere, whenever you're dealing with "extreme engineering" you're probing the limits of technology, and there will be unexpected problems to tackle. Even commercial firms, such as Airbus have experienced that.

On the other hand, it's worth noting how unmanned space exploration has advanced our knowledge of the Solar System and the cosmos at a far shorter budget than manned exploration.

Come mid-August, and even the first light would be all too overwhelming!

Every star, star cluster, galaxy, galaxy cluster, and so on, is surrounded by a gamma-ray halo. (The present gamma-ray bursts and the diffuse gamma-ray cosmic background that we detect are merely indicators to the fact.) Take note. It’s a gamma-ray jungle out there, with absolutely no dark matter, black holes or Hawking Radiation! And it’s all part of that ultimate model on the nature of things; see www.sittampalam.net/StarFormation.htm. Thank you.

No I don't know "full well" that the LHC will start in July. And neither do you. See this link and see if you are still so sure. hcc.web.cern.ch…

And just getting a beam in it is not a start even though advertised as such. If collisions at design energy follow after 1 year, the true start is in one year.

Quote:

Originally posted by jjeherrera

Quote:

Originally posted by andreicio

Ahhh ... it is pleasure to see the succesful launch of this mission. this is true science. Guys, stop worrying about the micro black holes at the LHC. It will never start operating. I thought the latest schedule had it taking beam in May. It's almost mid June and the beam is a distant prognostication. I don't know how most of the people there get to keep their jobs. In any other industry they would have been fired a long time ago. Especially Aymar who makes false statements (knowing htat they are false) to the media about the start dates.

It would be a thing of exquisite perversity if GLAST finds dark matter evidence before the LHC.

You know well that the LHC is scheduled to start operation in July (physicsworld.com…33600 ), and Aymar is no longer the director. As I mentioned elsewhere, whenever you're dealing with "extreme engineering" you're probing the limits of technology, and there will be unexpected problems to tackle. Even commercial firms, such as Airbus have experienced that.

On the other hand, it's worth noting how unmanned space exploration has advanced our knowledge of the Solar System and the cosmos at a far shorter budget than manned exploration.

No I don't know "full well" that the LHC will start in July. And neither do you. See this link and see if you are still so sure. hcc.web.cern.ch…

And just getting a beam in it is not a start even though advertised as such. If collisions at design energy follow after 1 year, the true start is in one year.

The web page you give is excellent to illustrate my point; it shows the complexity of tunning up all the systems, and how advancements are being made to reach the ultimate goal. What I see there are hard working people solving difficult engineering problems.

The incopetent often blame the difficulty of their task and the quality of their tools.

What you personally chose to see is your business. But what you are actually looking at is a mismanaged project run into the ground by people who care nothing of science but are obsessed with their pay checks and job stability. This is why Europe allways was and allways will be Number 2.

Quote:

Originally posted by jjeherrera

Quote:

Originally posted by andreicio

No I don't know "full well" that the LHC will start in July. And neither do you. See this link and see if you are still so sure. hcc.web.cern.ch…

And just getting a beam in it is not a start even though advertised as such. If collisions at design energy follow after 1 year, the true start is in one year.

The web page you give is excellent to illustrate my point; it shows the complexity of tunning up all the systems, and how advancements are being made to reach the ultimate goal. What I see there are hard working people solving difficult engineering problems.

The incopetent often blame the difficulty of their task and the quality of their tools.

What you personally chose to see is your business. But what you are actually looking at is a mismanaged project run into the ground by people who care nothing of science but are obsessed with their pay checks and job stability. This is why Europe allways was and allways will be Number 2.

Yes in physics. I bet the Tevatron will find the Higgs first. If they have not done so already and are just waiting for a strategic time to anounce the results. That will make those Champagne bottles taste bitter at CERN. Cheers!

Quote:

Originally posted by jjeherrera

Quote:

Originally posted by andreicio

The incopetent often blame the difficulty of their task and the quality of their tools.

What you personally chose to see is your business. But what you are actually looking at is a mismanaged project run into the ground by people who care nothing of science but are obsessed with their pay checks and job stability. This is why Europe allways was and allways will be Number 2.